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Biofuels and Climate Change Mitigation: A CGE Analysis Incorporating Land-Use Change . Govinda R. Timilsina The World Bank, Washington, DC 34 th IAEE International Conference Stockholm, Sweden June 19-22, 2011. Disclaimer.
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Biofuels and Climate Change Mitigation: A CGE Analysis Incorporating Land-Use Change Govinda R. Timilsina The World Bank, Washington, DC 34th IAEE International Conference Stockholm, Sweden June 19-22, 2011
Disclaimer The views expressed in this presentation are those of the authors only, and do not necessarily represent the World Bank and its affiliated organizations
Presentation Outline • Introduction/motivation • Brief overview of the model/data • Simulated policies • Key results • Conclusions
Introduction/Motivation • One of stated rationales to promote biofuels in most countries is its role in climate change • Do biofuels help mitigate climate change? A long ongoing debate in the literature • When emissions from indirect land-use change are accounted for the answer is uncertain, perhaps depends on what timeframe an analysis considers. Searchinger et al. (2008) - 167 years Fargione et al. (2008) - 48 years (corn ethanol in the US); over 300 years (Amazonian rainforest for soybean), over 400 years (tropical peat land rainforest for palm-oil in Indonesia or Malaysia) Danielsen et al. (2009)] - 75 to 93 years • Our study investigates the effects of large-scale expansion of biofuels on GHG emissions, accounting for both the reduction of fossil fuel based emissions and the increase in emissions through land-use change
Methodology • Multi-sector, multi-region, global recursive dynamic CGE model • The model is flexible enough to accommodate new regions/countries or sectors and is calibrated with GTAP database • Nested CES and CET functional forms to represent production behavior and land supply, respectively; • Non-homothetic Constant Difference of Elasticities (CDE) function form for households • Detailed representation of land-use and biofuel sectors • Representation of bilateral and international trade
Methodology (Continue …..) Figure 1: Nested CES structure of the model for production sectors
Methodology (Continue …..) Figure 2: Nested CET structure for land supply
Methodology (Continue …..) Figure 3: Nested CES structure of the model for energy demand
Data & Parameters • Data are coming from the GTAP (Global Trade Analysis Project) database (Purdue University, Indiana) • The database provides SAMs and international trade (bilateral flows, trade barriers) • Database version 7.1 • Year 2004 • 112 countries/regions • 57 sectors
Regional and sector decomposition • Computational limitations require aggregation of countries/regions and sectors (GTAP: 112 regions & 57 sectors or 112* 57 = 6,384 equations for 1 variable only defined on 2 dimensions) • Focus on main countries/regions producer of biofuels • Keep as much detail as possible for agriculture (especially biofuelfeedstocks) and for energy sectors
Base Year, Baseline and Scenarios • Base year: 2004 • Baseline or reference case: A business as usual scenario for 2009-2020 period. It includes policies already in place (e.g., already introduced mandates, subsidies) • The model is calibrated in such a way that key variables (e.g., oil prices, population, GDP, investments, etc.) retain the historical values for 2004-2009 period • Two scenarios for biofuel targets: • Announced Targets (AT) scenario: all the announced biofuel targets are fully implemented by 2020, starting 2009 • Enhanced Targets (ET) scenario: all the announced biofuel targets are doubled (except for India – extremely high announced target) and fully implemented by 2020, starting 2009 • Biofuel targets are achieved by introducing direct subsidies to biofuels, the subsidies are financed through an increase of gasoline and diesel tax (government revenue neutrality)
Biofuel Expansion Simulated in the Study Regional (2020) Biofuel penetration Global The expansions are modeled as change in biofuels’ share in total liquid fuel consumption in road transportation (also defined as biofuels penetration) Brazil’s targets are very close to BAU scenarios; India’s announced target is already high, therefore we did not consider doubling of it for India in the ‘enhanced target ‘ scenario
Impacts on Annual Emissions Unit: Million Tonnes Net annual emission decreases overtime and becomes negative in 2023 despite the fact that the production of biofuels is still increasing
Biofuel penetration, GHG emissions and carbon payback period
Deforested Lands as Percentage of Available Pasture Land With exception of Thailand where available pasture land is very limited, deforested land represents a small fraction of the total pasture lands available.
GHG emissions: Deforestation vs. No-Deforestation (Million tCO2)
Conclusions • If biofuel mandates and targets are implemented by 2020 using crop feedstocks, and if both forests and pasture lands are used to meet the new land demands, GHG emissions released to the atmosphere would increase until 2043. • If the use of forest lands is avoided by channeling only pasture lands to meet the demand for new lands, a net reduction of GHG emissions would occur starting from 2021, a year after the assumed full implementation of the mandates and targets. • The marginal rate of deforestation (i.e., annual incremental deforestation) and corresponding land-use emissions decrease despite the fact that the annual production of biofuels increases.
THANK YOU Govinda R. Timilsina Sr. Research Economist (Climate Change & Clean Energy) Development Research Group The World Bank 1818 H Street, NW Washington, DC 20433, USA Tel: 1 202 473 2767 Fax: 1 202 522 1151 E-mail: gtimilsina@worldbank.org